Polyester, viscous mixture, process for preparing same and cosmetic composition

Mixture comprising:

• a) at least one polyester resulting from a reaction between at least one dicarboxylic acid dimer and at least one alcohol bearing at least two hydroxyl functions, the at least one polyester having a viscosity of at least 200,000 cSt (mm2·s−1) at 40° C. and a hydroxyl index of less than 30 mg KOH/g, said viscosity being determined using an automatic Brookfield type viscometer, the type of spindle and the speed of the spindle being adapted to the measurement range, and said hydroxyl index being measured according to the NF ISO 4629-2 method,
• b) at least one biosourced hydrocarbon compound, namely a compound formed essentially, or even consisting of, carbon and hydrogen atoms, and optionally oxygen and nitrogen atoms, wherein the organic carbon present in said compound is 100% of plant origin (14C) by radiocarbon analysis according to one of the following standards ASTM D6866, EN 16640 or EN 16785-1,
• and said mixture being wherein the mass percentage of the at least one polyester is at least 50% relative to the total mass of the mixture and the mass percentage of the at least one biosourced hydrocarbon compound is at least 5% relative to the total mass of the mixture.